NUTRITIVE MANURES. 57 



combined with gelatine, passes into plants, that we can 

 attribute the wonderful effect produced upon vegetation 

 by certain dry animal substances, of which we shall speak 

 presently. 



Next to the dung of animals, of which I have just 

 spoken, the urine of horned cattle and of horses is the 

 most abundant manure which can be used in agriculture ; 

 and it is not without regret that I see every day so little 

 pains taken to collect it. I have already observed, that 

 in those countries where agriculture is conducted with the 

 most care and skill, all the stables are floored, and the 

 bottoms of them gently sloping, so as to conduct all the 

 urine into a reservoir, where the remains of rape-seed, 

 flax, wild cabbage, human excrements, &c. &.c. are thrown 

 into it to undergo fermentation. In the spring, when 

 vegetation begins to be developed, this fermented liquor 

 is carried into the fields to water the crops. 



There are few animal substances of which the nature 

 varies as much as that of urine; the quality of food, or 

 the state of health, produces a sensible change in it. 

 The urine of animals is more or less abundant and active 

 in its qualities, in proportion as their food is juicy or dry. 

 Those which live upon dry fodder give less urino than 

 those which are fed upon green herbage ; but that of the 

 first contains a greater quantity of salts than that of the 

 last; and that which is produced directly by drink, con- 

 tains less animal matter than that which is secreted from 

 the blood by the urinary organs. There are different 

 states of individuals, which may explain satisfactorily the 

 disagreements in the results which have been given, by 

 the numerous analyses which have been made of this 

 fluid. 



Mr. Brandt has found the urine of a cow to contain, 



Water 65 



Phosphate of lime 5 



Muriate of potash and of ammonia . . 15 



Sulphate of potash 6 



Carbonate of potash and of ammonia . 4 

 Urea 5 



100 

 Messrs. Fourcroy and Vauquelin have extracted from 

 that of the horse, 



